CVE-2021-22140 : What You Need to Know

Elastic App Search versions after 7.11.0 and before 7.12.0 are impacted by an XML External Entity Injection (XXE) vulnerability in the App Search web crawler beta feature. This vulnerability could permit an attacker to manipulate a malicious sitemap.xml to access sensitive files on the host system.

Understanding CVE-2021-22140

This section delves into the details of the CVE-2021-22140 vulnerability.

What is CVE-2021-22140?

The CVE-2021-22140 vulnerability affects Elastic App Search versions between 7.11.0 and 7.12.0, enabling an attacker to exploit an XML External Entity Injection issue in the App Search web crawler beta feature. Attackers can potentially access confidential files by crafting a malicious sitemap.xml.

The Impact of CVE-2021-22140

The presence of this vulnerability poses a severe threat as it allows unauthorized access to sensitive data, potentially leading to data leaks and unauthorized information disclosure.

Technical Details of CVE-2021-22140

This section provides insight into the technical aspects of the CVE-2021-22140 vulnerability.

Vulnerability Description

The vulnerability arises due to improper restriction of XML External Entity References, opening the door for attackers to exploit the App Search web crawler beta feature in affected Elastic App Search versions.

Affected Systems and Versions

Elastic App Search versions after 7.11.0 and before 7.12.0 are specifically impacted by this vulnerability.

Exploitation Mechanism

By manipulating a sitemap.xml file, attackers can trick the App Search web crawler into accessing and retrieving sensitive files from the host system.

Mitigation and Prevention

In light of CVE-2021-22140, it is crucial to take immediate action to prevent exploitation and enhance overall system security.

Immediate Steps to Take

Users are advised to update their Elastic App Search installations to versions 7.12.0 or later to mitigate the risk of exploitation. Additionally, monitoring system logs for any suspicious activities can help detect potential attacks.

Long-Term Security Practices

Implementing strict input validation mechanisms and ensuring regular security audits are essential for preventing such vulnerabilities in the future.

Patching and Updates

Regularly applying security patches released by Elastic for Elastic App Search can help in addressing known vulnerabilities and bolstering system defenses.